2004 Relay / Boxer cutting out

[CitroenCrazy]

Hi All

I'm posting this on behalf of my brother in law, who's having a nightmare with his camper van, which is also his daily driver.
It's a 2004 Peugeot Boxer / Citroen Relay with 2.2 HDi engine.

The problem is that it cuts out intermittently, and after paying various people to change various parts, he's no closer to a solution.

It's been going on a while, and although at the start, he thought it was happening at random, he's narrowed down the circumstances to the point where he can almost provoke the fault. Typically, it's when the engine is warmed up and he's been cruising for say 15 - 20 miles, and then, when you want to accelerate reasonably hard, say at a roundabout, - that's when the engine will die.
In the early days, it would restart quickly and easily on a turn of the key, but he says it's getting harder to restart it now.
The vehicle never seems to struggle to start from cold.

So far, the in-tank lift pump, the "pressure control valve on the HP pump" (????) and the pressure sensor have been changed.
Diagnostic codes read suggest an intermittent fuel pressure problem.

He's taken it to more than one diesel specialist, but apart from vague theries about injectors, nobody seems to have much idea, and he's running out of both patience and cash.

What I know about diesel engines could be written on the head of a pin with a paintbrush, but nonethleless, the fact it only happens when the engine's hot and under reasonable load makes me wonder about EGR ?
Otherwise, to me, it sounds more electrical than mechanical. Or could it be as simple as a blocked filter ? I don't know, and uninformed opinion counts for little here.

I don't mean to make this one of those "please diagnose this fault with 100% accuracy based on patchy and unrelaliable information" queries, but maybe someone could suggest some diagnostic tests or the best plan of attack.

TIA

Andrew

[Hell Razor5543]

There is a pressure regulator somewhere on the fuel system. Although I do not personally know where it is I have read (here on the forum) that this can cause symptoms similar to those described. There is a very fine filter in the regulator, and if this gets restricted it can cause poor fuel flow into the high pressure systems.

Give it time, and somebody with a lot more knowledge that I will be able to give you better pointers.

[jgra1]

Both my 2.0 c5 and my 2.2 2004 boxer camper cut out under load.

Both times an injector was faulty.

A leak off test for your friend it is almost free and may take about one hour .. take before and after pics for all ?

[GiveMeABreak]

And further to what John has said ^ did you get it diagnosed with Lexia? Those codes are key to what is going on - and if a Lexia is used they should be able to get some live readings from the injection system / injectors. That and any codes will help - replacing parts at random won't though I'm afraid.

[CitroenCrazy]

Thanks guys, very grateful for your input.
Although I have a Lexia / Diagbox, my brother in law is a way away from me, so I haven't checked his van with it yet.
I think a Snap On code reader has been used on it so far, and the only code obtained is intermittent fuel pressure - which covers a myriad of possibilities.

[wheeler]

I second a faulty injector, a leak off test will show a dodgy injector a mile away.
Assuming the fuel filter is good of course.

[jgra1]

Just 4 empty plastic bottles and some tube proper Blue Peter stuff ..

[myglaren]

Just 4 empty plastic bottles and some tube proper Blue Peter stuff ..

Credit: Jaguar Forum

There are youtube videos showing the procedure.


Just one example.

[Peter.N.]

If its anything like the C5 car I had this problem of it cutting out for no particular reason but evnetually noticed it only happened when I had been down a hill and tried to accelerate up the other side, it would cut out but if I turned the ignition off and waited for few minutes it would start again.

One day it did it when I was coming in down a steep forest track and I noticed just as it cut out the low oil pressure light just blinked briefly, I checked the oil and it was a little low, perhaps by a litre, I topped it up, no more trouble until it got low again. There is obviously a low oil pressure sensor, this was what was causing the problem with mine.

The regulator that can give problems is on the back of the HP diesel pump, not to difficult to change.

Peter

[CitroenCrazy]

Thanks guys. Peter, I would never have guessed at oil pressure. Another lead to follow uo.
Cheers
Andrew

[CitroenCrazy]

Hi guys

Just in case someone else suffers the same problem, I can close the loop on this one now.

I caught up with my brother in law yesterday. The final diagnosis was 2 faulty injectors. After replacing those, normal service has been resumed.

Looks like the "specialist diesel mechanic" he took it to wasn't the best, as he only did a leak-off test after replacing other parts first; if that had been step one, it woudl have been a much quicker and cheaper experience.

Thanks to all who offered advice.

[jgra1]

good news eventually, crazy